Search results for " set"

showing 10 items of 2095 documents

Social Influence Maximization in Hypergraphs

2021

This work deals with a generalization of the minimum Target Set Selection (TSS) problem, a key algorithmic question in information diffusion research due to its potential commercial value. Firstly proposed by Kempe et al., the TSS problem is based on a linear threshold diffusion model defined on an input graph with node thresholds, quantifying the hardness to influence each node. The goal is to find the smaller set of items that can influence the whole network according to the diffusion model defined. This study generalizes the TSS problem on networks characterized by many-to-many relationships modeled via hypergraphs. Specifically, we introduce a linear threshold diffusion process on such …

Hypergraphsocial networksSelection (relational algebra)Computer scienceGeneralizationScienceQC1-999hypergraphGeneral Physics and Astronomy02 engineering and technologyAstrophysicsArticlehigh-order networkSet (abstract data type)influence diffusion020204 information systems0202 electrical engineering electronic engineering information engineeringDiscrete mathematicshigh-order networks; hypergraphs; influence diffusion; social networks; target set selectionPhysicsQMaximizationQB460-466high-order networkshypergraphstarget set selectionGraph (abstract data type)020201 artificial intelligence & image processingNode (circuits)Heuristics
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Fuzzy Non-fragile H∞ Tracking Control for Flexible Air-breathing Hypersonic Vehicles

2012

Abstract This paper proposed a fuzzy non-fragile tracking control design method for flexible air-breathing hypersonic vehicles (FAHVs). The T-S fuzzy set approach is applied to the modeling of the complex nonlinear dynamics of FAHVs, and a T-S fuzzy model is constructed, which can represent the nonlinear hypersonic vehicle system. Then, by considering the actuator controller coefficients uncertainties and disturbances, the fuzzy non-fragile H ∞ tracking problem for FAHVs is proposed. A state-feedback controller design method is proposed to guarantee the tracking performance in the presence of actuator controller coefficients uncertainties. By a Lyapunov approach, the existence conditions fo…

Hypersonic speedEngineeringNonlinear systemControl theorybusiness.industryControl (management)Fuzzy setControl engineeringActuatorbusinessTracking (particle physics)Fuzzy logicIFAC Proceedings Volumes
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An ab initio study of the unimolecular decomposition mechanism of formamidine. 4-31G Characterization of potential energy hypersurface

1991

Ab initio MO calculations have been carried out for the unimolecular decomposition of formamidine. The Hartree–Fock method in LCAO approximation with the 4-31G basis set was used. The 4-31G potential hypersurface has been further studied. The stationary points (R, TS, and P) were localized. A reaction analysis by correlation of bond-order indices and localized molecular orbitals demonstrated that the decomposition is an asynchronous process. The TS can be described as four-membered ring.

HypersurfaceLinear combination of atomic orbitalsChemistryComputational chemistryAb initioLocalized molecular orbitalsPhysical and Theoretical ChemistryCondensed Matter PhysicsRing (chemistry)Stationary pointDecompositionAtomic and Molecular Physics and OpticsBasis setInternational Journal of Quantum Chemistry
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Champs de vecteurs analytiques et champs de gradients

2002

A theorem of Łojasiewicz asserts that any relatively compact solution of a real analytic gradient vector field has finite length. We show here a generalization of this result for relatively compact solutions of an analytic vector field X with a smooth invariant hypersurface, transversally hyperbolic for X, where the restriction of the field is a gradient. This solves some instances of R. Thom's Gradient Conjecture. Furthermore, if the dimension of the ambient space is three, these solutions do not oscillate (in the sense that they cut an analytic set only finitely many times); this can also be applied to some gradient vector fields.

HypersurfaceRelatively compact subspaceApplied MathematicsGeneral MathematicsMathematical analysisGradient conjectureVector fieldAnalytic setInvariant (mathematics)MathematicsAmbient spaceErgodic Theory and Dynamical Systems
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Ethno Therapy, Music and Trance: An EEG Investigation into a Sound-Trance Induction

2011

Music has been used since ancient times in healing rituals. It has been played for people to induce altered states of consciousness (ASC), which change the focus of attention, mood, and thoughts about the world and the self. Music and altered states are connected in various ways concerning context, personal set, socio-ecological setting, and cultural beliefs. Discussion is ongoing as to whether music itself induces the changes via a “trance mechanism” or whether the setting and rituals connected to music are responsible for the induction of ASC. The authors conducted an explorative attempt to represent interdependencies of set and setting, sound and trance through electrophysiological corre…

HypnosisPsychotherapistMusic therapymedicine.diagnostic_testSelfmedia_common.quotation_subjectTranceElectroencephalographyMoodSet and settingmedicineConsciousnessPsychologyCognitive psychologymedia_common
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Fuzzy Concepts in Small Worlds and the Identification of Leaders in Social Networks

2014

In the study of the Social Networks, the Small World phenomenon appears frequently. We apply some techniques of graph theory and fuzzy sets to characterize the Small World features as well as the existence of the figure of leader in Social Networks. These techniques help to the conceptual formalization in relational networks analysis, by transforming linguistic and human-focused manner concepts related to social networks in some formal representation. These techniques are also applied when the similarity among nodes wants to be measured in order to study the current homophily present in a Network.

Identification (information)Social networkbusiness.industryManagement scienceComputer sciencePhenomenonFuzzy setSimilarity (psychology)Graph theorybusinessFuzzy logicData scienceHomophily
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INDUCTIVE INFERENCE OF LIMITING PROGRAMS WITH BOUNDED NUMBER OF MIND CHANGES

1996

We consider inductive inference of total recursive functions in the case, when produced hypotheses are allowed some finite number of times to change “their mind” about each value of identifiable function. Such type of identification, which we call inductive inference of limiting programs with bounded number of mind changes, by its power lies somewhere between the traditional criteria of inductive inference and recently introduced inference of limiting programs. We consider such model of inductive inference for EX and BC types of identification, and we study • tradeoffs between the number of allowed mind changes and the number of anomalies, and • relations between classes of functions ident…

Identification (information)Theoretical computer scienceBounded functionComputer Science (miscellaneous)Fiducial inferenceProbabilistic logicInferenceFunction (mathematics)Inductive reasoningFinite setAlgorithmMathematicsInternational Journal of Foundations of Computer Science
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Identification and validation of quasispecies models for biological systems

2009

An identification procedure for biological systems cast as quasi-species models is proposed. Their identification is a challenging problem because of the bilinear dependence on the parameters and their physical constraints. The proposed solution is within the framework of set-membership identification. %The bilinear dependence on parameters of the model and their physical constraints make the present issue challenging. We determine an estimate of the model parameters together with their interval of variability (Uncertainty Intervals), taking into account all the physical constraints. Invalidation/validation is performed on the basis of the predictive capability of the estimated models. The …

IdentificationGeneral Computer ScienceBasis (linear algebra)Systems Biology; Identification; Validation; Set MembershipComputer scienceSystems BiologyMechanical EngineeringSystems biologySystem identificationBilinear interpolationViral quasispeciesInterval (mathematics)Set MembershipSystems Biology Identification Validation Set MembershipSet (abstract data type)Identification (information)Settore ING-INF/04 - AutomaticaControl and Systems EngineeringValidationElectrical and Electronic EngineeringAlgorithm
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Corso di diritto internazionale

2023

Serving as a single-volume introduction to international law, the book seeks to present international law as a system characterized by an ongoing process of sectoralization and institutionalization.

Il volume intende fornire una introduzione completa al diritto internazionale presentandolo come caratterizzato da un processo ancora in corso di settorializzazione e istituzionalizzazione.Settore IUS/13 - Diritto Internazionale
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The role of perceptual contrast non-linearities in image transform quantization

2000

Abstract The conventional quantizer design based on average error minimization over a training set does not guarantee a good subjective behavior on individual images even if perceptual metrics are used. In this work a novel criterion for transform coder design is analyzed in depth. Its aim is to bound the perceptual distortion in each individual quantization according to a non-linear model of early human vision. A common comparison framework is presented to describe the qualitative behavior of the optimal quantizers under the proposed criterion and the conventional rate-distortion based criterion. Several underlying metrics, with and without perceptual non-linearities, are used with both cr…

Image codingTraining setbusiness.industryQuantization (signal processing)media_common.quotation_subjectComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISIONPerceptionSignal ProcessingComputer visionComputer Vision and Pattern RecognitionArtificial intelligencePerceptual DistortionMinificationbusinessAlgorithmMathematicsmedia_commonImage and Vision Computing
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